diff options
Diffstat (limited to 'fs/btrfs/qgroup.c')
| -rw-r--r-- | fs/btrfs/qgroup.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index f41da7ac360d..da1f84a0eb29 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -1232,12 +1232,23 @@ int btrfs_quota_disable(struct btrfs_fs_info *fs_info) int ret = 0; /* - * We need to have subvol_sem write locked, to prevent races between - * concurrent tasks trying to disable quotas, because we will unlock - * and relock qgroup_ioctl_lock across BTRFS_FS_QUOTA_ENABLED changes. + * We need to have subvol_sem write locked to prevent races with + * snapshot creation. */ lockdep_assert_held_write(&fs_info->subvol_sem); + /* + * Lock the cleaner mutex to prevent races with concurrent relocation, + * because relocation may be building backrefs for blocks of the quota + * root while we are deleting the root. This is like dropping fs roots + * of deleted snapshots/subvolumes, we need the same protection. + * + * This also prevents races between concurrent tasks trying to disable + * quotas, because we will unlock and relock qgroup_ioctl_lock across + * BTRFS_FS_QUOTA_ENABLED changes. + */ + mutex_lock(&fs_info->cleaner_mutex); + mutex_lock(&fs_info->qgroup_ioctl_lock); if (!fs_info->quota_root) goto out; @@ -1301,7 +1312,9 @@ int btrfs_quota_disable(struct btrfs_fs_info *fs_info) goto out; } + spin_lock(&fs_info->trans_lock); list_del("a_root->dirty_list); + spin_unlock(&fs_info->trans_lock); btrfs_tree_lock(quota_root->node); btrfs_clear_buffer_dirty(trans, quota_root->node); @@ -1317,6 +1330,7 @@ out: btrfs_end_transaction(trans); else if (trans) ret = btrfs_end_transaction(trans); + mutex_unlock(&fs_info->cleaner_mutex); return ret; } |